The Microfin technology used in the Model-O heatsink is quite simple from the outset.
Small flaps of copper have been skived from a flat plate of copper to form fins
which stand upright, creating a seamless thermal joint. With the Dynatron Model-O, both fins and base are made from one solid piece of copper - there are no joints whatsoever. The only component
attached to the one-piece heatsink is the aluminum shroud used to support the fan,
and direct airflow down into the fins.

Now we've
seen similarly formed heatsinks before (ie. the aluminum AVC Skive),
but so far none have had anywhere near the same degree of fin density. In fact
the Model-O boasts sixty 0.35mm thick copper fins set at a pitch of 1.0mm.
The high-density fin design creates a larger amount
of surface area to diffuse heat to the surrounding environment, and should theoretically make this a
more efficient heatsink.

Wondering about these Copper Microfins we speak of? From what we can gather about
the manufacturing process (it is still somewhat of an industrial secret), the process goes something analogous
to a chisel cutting into a piece of wood. The difference is that
the cuts are much more controlled, and result in straight bits of metal (the fins) standing
in an upright position.

While that sounds relatively simple, the machine used to make these rather unique
heatsinks cost a cool quarter million, and is one of only a few that can mange
such a high fin pitch apparently. Dynatron tell us that their yield on these
heatsinks is only around 50%-60% because an entire heatsink becomes scrap if any of the effectively
120 fins is accidentally chipped off.

After removing the aluminum shroud we were
able to take a first hand look at these fins. Each fin has a smooth side,
and a rough side. The tips of the fins come to a
knife edge, and unlike what you might expect from copper are nice and stiff - probably
due to work hardening.

Rough Side

Smooth Side

If we look very closely at the fins for a moment you can
see two aspects that are kind of interesting. First off is the fact that each
fin is cut from the same copper plate that makes up the base of the
heatsink.

The
other is the bumpy surface of one side of each fin. From
the best of my knowledge, the bumps come from the shearing forces that cause
the skive of copper to be forced up. Those forces cause distortions on the other
side of the copper fin that correlate to the internal crystalline structure
of the metal. The lower-righthand picture also illustrates the knife edge
on the top of the fin I was speaking about. This feature should lessen the resistance
to air flowing down in between the fins.